Placental abruption happens when the placenta separates from the inner wall of the womb, also called the uterus. The cause is often unclear. But it can happen due to an injury to the stomach area, such as from a car crash or a fall. It also can happen if the womb quickly loses amniotic fluid, the clear liquid that surrounds and cushions the baby.

Placental abruption can cause bleeding from the vagina and pain in the stomach area or back. The stomach area may feel tender or rigid. Feelings of tightness and relaxing in the womb, called contractions, also may happen. The symptoms are most likely to start in the last three months of pregnancy, mainly in the final few weeks before birth.

If it's too soon for the baby to be born, the pregnancy might need to be monitored at the hospital. The mother may need to take medicines that help the baby's lungs and brain. If the baby is close to full term, a vaginal birth or a faster delivery method such as C-section may be an option. The mother may need a blood transfusion for serious bleeding.